Radiation shields of the type comprising a container formed of thin flexible material filled with a radiation attenuating liquid were originally disclosed in my U.S. Pat. No. 4,090,087, issued May 16, 1978. Such radiation shields have come into widespread use. However, despite their popularity, their use has presented certain problems, particularly in properly filling and emptying the shields.
The radiation shields are stored in a collapsed condition, and, when it is desired to use one, it is taken out and filled with a radiation attenuating liquid, such as a hydrogeneous liquid. If the filling takes place remote from the radiation source, it is sometimes difficult to move the heavy and unwieldy filled shield into place adjacent to the radiation source. And, if the filling takes place adjacent to the radiation shield, the radiation shield sometimes unfolds and extends in unpredictable, exasperating, and potentially dangerous directions and orientations as the attenuating liquid is pumped into the shield, causing the shield to gradually take on its filled shape.
When it is desired to empty a radiation shield of this type, the common practice has been to open a liquid drain valve at the bottom and to allow the liquid to drain out. This practice has required lengthy waits, and the drainage is not always complete because there is only atmospheric pressure and/or mechanical manipulations of the bag to force the liquid out. Alternatively, in situations where the radiation shield is connected to a recycling system for the radiation attenuating liquid, such as is disclosed in my U.S. Pat. No. 4,090,087, the pump is either turned off or reversed, but the drainage is still quite slow.